A large body of literature exists demonstrating the exposure, uptake, and presence of micro- and nanoplastic particles (MNPs) within marine biota. Despite this, there remain challenges in synthesizing these studies in a consistent and reliable manner which can support technology, regulatory, and policy decision-making. The most significant challenge is a lack of guidance to assess and integrate study reliability (objective quality) and relevance (ability to answer a specific question).
View Article and Find Full Text PDFRecent toxicity studies of stormwater runoff implicated N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-quinone) as the contaminant responsible for the mass mortality of coho salmon (Oncorhynchus kisutch). In the wake of this discovery, 6PPD-quinone has been measured in waterways around urban centers, along with other tire wear leachates like hexamethoxymethylmelamine (HMMM). The limited data available for 6PPD-quinone have shown toxicity can vary depending on the species.
View Article and Find Full Text PDFThe potential for oil spills poses a threat to marine organisms, the toxicity of which has been attributed primarily to polycyclic aromatic compounds (PACs). Predictive tools such as the target lipid model (TLM) have been developed to forecast and assess these risks. The aim of the present study was to characterize the cardiotoxicity of 10 structurally diverse PACs in American lobster (Homarus americanus) larvae by assessing heart rate following a 48 h exposure in a passive dosing system, and subsequently use the TLM framework to calculate a critical target lipid body burden (CTLBB) for bradycardia.
View Article and Find Full Text PDFPolycyclic aromatic compounds (PACs) present in the water column are considered to be one of the primary contaminant groups contributing to the toxicity of a crude oil spill. Because crude oil is a complex mixture composed of thousands of different compounds, oil spill models rely on quantitative structure-activity relationships like the target lipid model to predict the effects of crude oil exposure on aquatic life. These models rely on input provided by single species toxicity studies, which remain insufficient.
View Article and Find Full Text PDFImmune checkpoint inhibitors are known to have a wide range of autoimmune toxicities, such as acute interstitial nephritis. Immunotherapy induced glomerulonephritis has been described, but anti-glomerular basement membrane disease (anti-GBM) is rarely reported. We present a case report of a 60-year-old woman with squamous cell carcinoma of the cervix who was treated with pembrolizumab, an anti-programmed cell death protein 1, and who developed severe acute kidney injury 4 months after therapy initiation.
View Article and Find Full Text PDFOil spill risk and impact assessments rely on time-dependent toxicity models to predict the hazard of the constituents that comprise crude oils and petroleum substances. Dissolved aromatic compounds (ACs) are recognized as a primary driver of aquatic toxicity in surface spill exposure scenarios. However, limited time-dependent toxicity data are available for different classes of ACs to calibrate such models.
View Article and Find Full Text PDFBackground: The vitamin A derivative all-trans retinoic acid (RA) regulates early stages of inner ear development. As the early disruption of the RA pathway results in profound mispatterning of the developing inner ear, this confounds analyses of specific roles in later stages. Therefore, we used the temporal-specific exposure of all-trans RA or diethylaminobenzaldehyde to evaluate RA functions in late otic development.
View Article and Find Full Text PDFDiluted bitumen, also known as dilbit, is transported by rail and pipeline across Canada and the United States. Due to the fewer number of studies characterizing the toxicity of dilbit, a dilbit spill poses an unknown risk to freshwater aquatic ecosystems. In the following study, we compared the impact of early-life exposure to conventional and unconventional crude oils on the optomotor behavior, reproductive success, and transgenerational differences in gene expression in zebrafish and their progeny.
View Article and Find Full Text PDFAquatic exposures to aromatic compounds (ACs) may be important contributors to biological effects of oil spills. The present study examined the acute toxicity of 11 ACs and 3 binary AC mixtures on stage 1 American lobster larvae using a passive dosing test design. The ACs investigated covered a range of classes and log octanol-water partition coefficient values (K ; 2.
View Article and Find Full Text PDFUltraviolet (UV) filters are compounds utilized in many manufacturing processes and personal care products such as sunscreen to protect against UV-radiation. These highly lipophilic compounds are emerging contaminants of concern in aquatic environments due to their previously observed potential to bioaccumulate and exert toxic effects in marine ecosystems. Currently, research into the toxic effects of UV filter contamination of freshwater ecosystems is lacking, thus the present study sought to model the effects of acute and chronic developmental exposures to UV filters avobenzone, oxybenzone and octocrylene as well as a mixture of these substances in the freshwater invertebrate, Daphnia magna, at environmentally realistic concentrations.
View Article and Find Full Text PDFThe Deepwater Horizon oil spill released 3.19 million barrels of crude oil into the Gulf of Mexico, making it the largest oil spill in U.S.
View Article and Find Full Text PDFBackground: Atypical hemolytic uremic syndrome (aHUS) is an extremely rare, heterogeneous disease of uncontrolled activation of the alternative complement pathway that is difficult to diagnose. We have evaluated the Canadian patients enrolled in the Global aHUS Registry to provide a Canadian perspective regarding the diagnosis and management of aHUS and the specific challenges faced.
Objective: To evaluate Canadian patients enrolled in the Global aHUS Registry to provide a Canadian perspective regarding the diagnosis and management of aHUS and the specific challenges faced.
Exposure to oil sands process-affected water (OSPW), a by-product of Canadian oil sands mining operations, can cause both acute and chronic adverse effects in aquatic life. Ozonation effectively degrades naphthenic acids in OSPW, mitigating some of the toxicological effects of exposure. In this study we examined the effect of developmental exposure to raw and ozonated OSPW had on the breeding success, prey capture, and alarm cue response in fish months/years after exposure and the transgenerational effect exposure had on gene expression, global DNA methylation, and larval basal activity.
View Article and Find Full Text PDFBackground: B-cell anomalies play a role in the pathogenesis of membranous nephropathy. B-cell depletion with rituximab may therefore be noninferior to treatment with cyclosporine for inducing and maintaining a complete or partial remission of proteinuria in patients with this condition.
Methods: We randomly assigned patients who had membranous nephropathy, proteinuria of at least 5 g per 24 hours, and a quantified creatinine clearance of at least 40 ml per minute per 1.
The Deepwater Horizon (DWH) oil spill was the biggest in US history and released 3.19 million barrels of light crude oil into the Gulf of Mexico. In this study, we compared the toxicity of water accommodated fractions (WAFs) of naturally weathered crude oils, source oil, and source oil with dispersant mixtures and their effects on developing sheepshead minnow and zebrafish.
View Article and Find Full Text PDFWith the ever-increasing amounts of oil sands process-affected water (OSPW) accumulating from Canada's oil sands operations, its eventual release must be considered. As OSPW has been found to be both acutely and chronically toxic to aquatic organisms, remediation processes must be developed to lower its toxicity. Ozone treatment is currently being studied as a tool to facilitate the removal of organic constituents associated with toxicity.
View Article and Find Full Text PDFDue to the increasing volume of oil sands process-affect water (OSPW) and its toxicity to aquatic organisms, it is important to fully understand its effects and study remediation processes that will enable its release to the environment. Ozone treatment is currently being considered as a tool to expedite remediation, as it is known to degrade toxic organic compounds present in OSPW. In this study, we aimed to measure the effects of OSPW exposure on the growth, development and recovery of zebrafish (Danio rerio) embryos.
View Article and Find Full Text PDFTo facilitate pipeline transport of bitumen, it is diluted with natural gas condensate, and the resulting mixture, "dilbit", differs greatly in chemical composition to conventional crude oil. Despite the risk of accidental dilbit release, the effects of dilbit on aquatic animals are largely unknown. In this study, we compared the toxicity of water accommodated fractions (WAFs) of dilbit and two conventional crude oils, medium sour composite and mixed sweet blend, to developing zebrafish.
View Article and Find Full Text PDFBackground: Idiopathic membranous nephropathy remains the leading cause of nephrotic syndrome in Caucasian adults. Immunosuppressive therapy with cyclosporine (CSA) is often successful in reducing proteinuria, but its use is associated with a high relapse rate. Rituximab, a monoclonal antibody that specifically targets CD20 on the surface of B-cells, is effective in achieving a complete remission of proteinuria in patients with idiopathic membranous nephropathy.
View Article and Find Full Text PDFNat Clin Pract Nephrol
October 2008
Membranous nephropathy, focal segmental glomerulosclerosis and IgA nephropathy are the most commonly recognized types of primary glomerulonephritis that progress to end-stage renal disease. Persistent proteinuria is a major determinant of such progression. Reduction of proteinuria slows progression of renal disease and improves renal survival, but many of the agents used to reduce proteinuria carry a considerable risk of toxicity.
View Article and Find Full Text PDFIgA nephropathy is the most common biopsy-proven pattern of glomerulonephritis in the world. Many factors, both clinical and histologic, have been suggested to impact on prognosis. We review the wide variations in how patients with immunoglobulin A nephropathy can present and the important differences derived from the clinical pathologic setting through the description of 4 cases.
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